Wire line core barrel



Sept. 21, 1943. L Q STQKES l l 2,330,157'

WIRELINE CORE BARREL Filed Aug. l, 1942 J0@L c. mes.

' INV ENT OR.

Patented Sept. 2l, 19,43`

wma LINE conn Banani.

John C. Stokes, Houston, Tex., asslgnor to Reed Roller Bit Company, Houston, Tex., a corpora tion ot Texas application august i, i942', serial Nafesaiso 'iz claims. (ci. 2155-72) This invention relates in general to wire line coring equipment and has for itsy general object the provision of such equipment, which will be.

simpler and more eective than wire line coring equipment has been in the past.

`In the past it has been generally the construction of wire line coring equipment that the core bit which is carried on the lower end of the drill stem is formed with the cutter means which is in ilxed position on the bit and which is disposed about the openings is adapted to be lowered through the drill stem. and seated within the core -bit so that its lower end may either lie within the core bit or protrude beyond the lower end of the core bit and have teeth thereon for the purpose of trimming the core. Thev core barrel is usually latched down by means of a latching device on its upper end that is adapted to engage with a` suitable part of the drill collar, to which the core bit is attached. It will readily be seen that with such a construction a special type and length of drill collar will be necessary and a special sub and driver will have to be provided for use there-4 with. With such an apparatus also it is customary when the core bit is to be used without vtaining a core, to remove the core barrel and to lower in place thereof a dummy tool, known as a center bit, this tool being latched in place in the same manner as the core barrel and having teeth on its lower end for the purpose of drilling the center of the hole and preventing the formation of a core. This, however, necessitates running the center bit in and out each time that the device is changed from one for 'taking a core to one for drilling a full hole and vice versa, and

` this change requires a substantial amount of Another object of this invention is to provide a structure which will cut more clearance around a core and thereby lessen the danger of balling the cutter head or burning the core.

to the bit. The core barrel Another object of this invention is to provide a structure which will cut faster than any heretofore known combination of cutter head and center bit.

Other objects and advantages of this invention will become apparent from the following description taken in connection with the accompanying drawing, wherein is illustrated by way of example one embodiment of this invention.

In the drawing:

Fig. 1 is a view partly in side elevation and partly in vertical cross section, illustrating a wire line coring apparatus constructed in accordance with this invention, the same being shown during the operation of takingv a' core.

Fig. 2 is a bottom plan. view of the structure illustrated in Figure 1. 4

Fig. 3 is a view similar to Fig.' 1 ybut illustrating the device in use when no core is being ltaken.

Fig. 4 shows the side elevation of the` device illustrated in Figs. 1 to'3 but taken lat right angles to Figs- 1 and 3.

With reference more particularly to the drawing, the numeral l indicates the body of the core bit, which is secured to the lower end of the drill stem. Adjacent its lower end; the bit l is provided with the laterally extending fish tail cutters or blades 3, which may be of somewhat usual construction, and at its lower end it is provided with cutting blades which serve to perform a normal operation of trimming the opening around the core as the core is being formed.

Just above the lower ends of the lblades the same are provided on their inner surfaces with a downwardly and inwardly tapered seat- 5, adapted 'to receive the lower tapered end 6 of the core barrel l. The tapered end 6 is formed on a head member, which is threaded at 8 to the core barrel proper,.and this head member is provided with a circumferential groove 9 against its lower end for purpose presently to be described.

The body I, at circumferentially spaced points, is provided with notches extending upwardly from its lower end, and in these notches are mounted by means of pivot pins Ill a plurality ofl swinging cutter blades, Il. These cutter blades which are adapted, when the core barrel is properly seated within .the core bit after blades Il are swung inwardly by the pivots, to engage within the circumferential groove 9 so as to hold the core barrel downwardly in its proper seated position within the core bit.

have projections I2'on their inner edges,

It will be seen that by virtue of thisconstruction the core barrel will be held downwardly in place within the core bit without the necessity for any latching mechanism such as is customarily provided near the upper end of the core barrel. This eliminates the necessity for any special drill collar, sub or driver. and at the same time makes it possible to more easily dislodge the core barrel when it is desired to remove the same.

Each of the blades l I is provided with an outer `edge surface I3, which is inclined downwardly and inwardly for all ordinary positions of the blade so that when the bit I is placed on the bottom of the well and rotated. these `blades II will tend to swing inwardly about their pivots I0. Thus, if the core barrel is in place within the core bit. they will tend to swing inwardly to the position illustrated in Fig.`1, in which position the projections I2 will engage the groove 9 to hold the core barrel in place. When the core barrel is not in place, the blades will tend to swing inwardly to the `position illustrated in Fig. 3, in which position they completely close the lower end of the opening through the core blt in so far as the formation of any c ore is concerned. so that as the drilling proceeds any core will not be formed but will be broken up by the blades I I. Y

Each of the blades II is also provided with a cutting edge I4. which is disposed most closely adjacent the axis of rotation of the core bit, and these cutting edges I4 will serve whenthe core barrel is in place and a coring operation is being carried out, to trim the outside surface of the core so that there will be ample clearance for the core to enter the core barrel.

At the upper end of the core barrel, las previously stated, there is no necessity for providing any 'latching mechanism such as heretofore employed, and hence the upper end of the core barrel is merely provided with a head I5, secured to the upper end of the core barrel by means of threads I6. This head I5 has at its upper end a spearhead I'I, which may be engaged by an overshot for the purpose of removing the core bar rel from the well, and at its lower end it is made hollow and adapted to receive a valve seat I8, held in place'by means of an appropriate holding nut I9. The valve seat I8 is`adapted to receive a downwardly seating ball valve 20, which is normally urged downwardly towards its seating position by means of a spring 2l. It will thus be seenthat this ball valve will serve to permit flow of uid upwardly from the core barrel during the taking of a core but will serve to prevent the downward flow oil-fluid into the core barrel due to the force of the slush being pumped through the drill stem from the surface of the ground'.

It will be seen from the foregoing that a structure has been provided which is capable of carrying out and accomplishing all of the objects and advantages sought by this invention. The operation of this device is briefly as follows:

The bit I will be lowered into a well on a drill stem in the usual manner, it being unnecessary. however, to provide special drill collars, subs or drives as is the usual practice in wire line coring apparatus. When it is desired to take a core, the core barrel 1 with its associated parts is dropped into the upper end of the drill stem and either pumped into place or lowered on a wire line until its lower end 6 seats within the seat s m the 'drin ba l. The drm bit 1s uien mwered against the bottom of the well and the drilling `operations begin. As hereinbefore described. the

blades I I will be swimg inwardly by contact with the bottom of the well and when they swing inwardly the projections I2 will engage within the circumferential groove 8 and thus latch the core barrel '|dowx1wardly and in 'its proper coring position, as illustrated in Fig. 1. f

When the coring operation has been completed, an overshot on a wire line may be lowered into the drill stem and brought in to engagement with the spearhead I1, in the well-known manner. T he drill bit I will be lifted from the bottom of the well so that the blades II will be free to swing outwardly and disengage the projections I2 from the groove 9, whereupon the core barrel will, of course, be free to move upwardly. The core barrel can then be removed from the well by means ofthe wire line with overshot attachedV and the core taken out of the core barrel for examination.

engagementof-the bladesl f'wth the bottom of the well will cause them to swing inwardly to the position illustrated in Fig. 3, in which position they will drill the center of the bottom of the well and prevent the formation of any core.

It has been found that with a device of the type just described the drilling can be carried out much faster than with any combination of core cutter head and center bit heretofore employed. Also, the blades II may be so designed that they will cut more clearance around the core during the coring operation and thereby greatly reduce the danger of balling up the cutter head or burning the core. Furthermore, in the event the core barrel fails to seat properly, there can be no burning of the cutter head because no core is being cut. On the other` hand, if the core barrel fails to seat properly the blades I I will swing inwardly in the position shown in Fig. 3, even though the core barrel may be in place just above its seat. Under these circumstances, of course, no core will be taken and none will be formed because it will be broken up by the blades II.

Having described my invention, I claim:

1. In a coring apparatus, a core bit, a removablecore barrel adapted to seat within said core bit and receive a core cut thereby, and a plurality of blades pivotally mounted on said core bit and adapted to swing inwardly toward the axis of said bit and cut away the core when said core bit is operated withoutl said core barrel in place therein, said core barrel when seated 'extending between said blades to hold them outon said core bit adapted to swing inwardly toward the axis thereof and engage said core barrel to hold it in place when said core bit is operated with the core barrel therein, and to swing further inwardly to prevent the formation of a core when said core bit is operated without the core barrel therein.

asedio? 3. h1 a coring apparatus, a core bit, aremovable core barrel adapted to seat within said core -bt and receive a core out thereby, and means on said core bit and engageable with the bottom of the hole to swing said means toward the axis of the bit and engage said core barrel to hold it in piace when said core bit is operated with the core barrel therein.

4. In a coring apparatus, a core bit, a removable core barrel adapted to seat within said core bit and receive a core out thereby, and blades pivotally mounted on said core bit and engageable with the 'bottom of the hole to swing said blades inwardly toward the aids of the bit and engage said core barrel to hold it in place when said core bit is operated with the core barrel therein.

5. in a ooring apparatus, a core bit, a remov-A bit and receive a core cnt thereby, and blades 2 on said core bit adapted to swing inwardly toward the axis thereof and engage said core barrel to hold it in place when saidbit is operated with the core barrel therein and to swing further inwardly to prevent the formation of a core when said core bit is operated without said-core .barrel therein.

8. In a coring apparatus, a core bit, a removable core barrel adapted to seat within said core bit and receive a core out thereby, and means on said core bit adapted to be swung inwardly by contact with the formation in a direction toward the axis of said core bit and to engage said core barrel to hold it in place when said core bit is operated with the core barrel therein, and to be swung inwardly still further by contact with the formation to prevent the formation oi a core when said core bit is operated without the core barrel therein.

7. In a ooring apparatus, a core blt, a removable core barrel adapted to seat within such core bit and receive a core cut thereby, and means on said core bit adapted to be swung inwardly by contact with the formation toward the axis of the core bit and to engage said core barrel and hold it in place when said core bit is operated with the core barrel therein.

8. In a coring apparatus, e. core bit, a removable core barrel adapted to seat within said core bit andrreoeive a core out thereby, and blades having inner core trimming edges pivotally mounted on said core bit and adapted to swing inwardly toward the axis thereof when brought into engagement with the formation at the bottom of a well, said blades and barrel having intertting parts thereon whereby when said blades are swung inwardly by engagement with the bottom of the well, the said parts will serve to latch maid core barrel in the core bit.

9. In a curing apparatus, a core bit, a removable core barrel adapted to seat within said core bit and receive a core out thereby, and blades pivotaliy mounted on said core bit and adapted to be swung inwardly by contact with the formation at the bottom of a well, said blades and barrel having interiitting parts thereon where o by when said blades are swung inwardly said parts will intert to latch said core barrel in place within said core. bit, and whereby `when said core bit is operated without said core barrel therein said blades will be swung inwardly into substantial engagement with each other to prevent the formation of a core.

i0. In a coring apparatus, a core bit, a removable core barrel adapted to seat within said core bit and receive a core out thereby, and blades Q on said core bit pivotally mounted thereon, said blades being shaped with a downwardly and inwardly inclined outer edge surface, whereby they will be swung inwardly toward the axis or said core bit when brought into contact with the bottom of a well hole so as to engage said core barrel and hold it in place when said core hit is operated with the core barrel therein.

11. In a corlng apparatus, a core bit, a removable Vcore barrel adapted to seat within said core 0 bit and receive :a core cut thereby, and blades pivote-ily mounted on said core bit, and having their outer edge surfaces inclined downwardly and inwardly toward the axis of said core bit, whereby when said blades are brought intocon- V35 tact with the formation at the bottom of a well they will tend to swing inwardly toward the axis of said core bit and to engage said core barrel to hold it'in place when said core bit is operated with the core barrel therein, and to swing further inwardly to prevent the formation of a core barrel therein.

12. in a eoring apparatus, a core bit, a removable core barrel adapted to seat within saidcore bit and having a. circumferential groove formed 45 therein adiacent to its lower end, blades pivotally mounted on said core bit and adapted to swing inwardly toward the axis thereof, said blades having projections thereon adapted to engage in said circumferential groove in the core barrel 501:0 hold said core barrel in place when said core 55 therein.

JOHN C. STOKES.

core when said core bit is operated without the 

